MTA focused on porting legacy enterprise applications to containers, not just as a way to liberate those apps from their original environments but as the first step in letting these apps be modernised or rewritten entirely. Containers can make that process less cumbersome, because developers do not have to wrestle with the limits of an underlying OS that can’t be updated.

The new Windows Server programme is in the same spirit, but it focuses on containerising and modernising apps for Windows Server. According to Docker, the process starts by figuring out what common dependencies those apps have — shared components and runtimes, as well as dependencies on services provided by a particular version of Windows Server. From there, any dependent components can also be containerised and upgraded along with the apps that use them.

One example is a system-level dependency where an app requires the existence of an earlier version of Microsoft’s Internet Information Server (IIS) web server. An app that uses a legacy edition of IIS can simply use a Microsoft-provided image for that component.

According to Docker, most of the apps likely to be ported with this service are legacy in-house apps written using Microsoft’s stack — .Net, C#, and Visual Basic applications — although some Java apps using the Windows runtime do figure into the mix.

The new service comes with the release of Docker Enterprise 2.1. Its new features include expanded support for Windows Server 2016 and 2019, more detailed dashboarding and management options, and support for SAML 2.0 authentication.